1. Field of the Invention
The present invention relates, in general, to the field of mobile computing and communication hand-held devices utilizing an information display, specifically to view navigation and scrolling of a stored virtual display or a magnified image of the display in response to changes of the orientation at which the device is held in one hand.
2. Description of the Related Art
The rapid miniaturization of complex electronic circuits and the emergence of high-resolution Liquid Crystal Displays have vastly increased the number and variety of smart hand-held devices with information displays. Such devices include hand-held computers, mobile telephones, pagers and other communication and computing solutions. The success of the Internet in recent years has further increased the need for mobile devices that provide a large amount of information to the user on the go.
The vast and varied contents of the Internet allow the user to access large chunks of information. Smart hand-held devices have undergone rapid improvement to enable them to communicate such information to the user. While the processing power, data storage capability, communication speed, and battery life of modern hand-held devices continue to develop at an accelerated pace, it seems that the information flow is limited by the small size of the display. It is clear however, that large displays that are used in desktop and laptop computers cannot be used in a small hand-held device.
Various approaches have been undertaken in order to overcome the display size limitation in hand-held information devices. Web Clipping is an approach taken by Palm Inc. to allow their commercially available Palm Series to browse the Internet. Web Clipping applications were developed for popular web sites, which respond to user's queries by clipping minimal information from the accessed sites in a typically textual form. The disadvantage of Web Clipping is that limited information is brought to the user, and not all web sites have the application to create the web clipping for the user. In many cases, even after clipping, the amount of available information is much more than can fit in one display view.
The use of optical magnification of a small display has been adopted for virtual reality helmets and other applications where the display is seated at a fixed distance from the user's eye. For example, U.S. Pat. No. 5,739,955 discloses such a virtual reality helmet with binocular magnifying optics. Optical magnifiers may appeal to persons with impaired vision who cannot view detailed information in a small hand-held display. However, the main problem with optical magnification when used with a hand-held device is the difficulty of use. Such a hand-held device and its associated optics must be placed at a relatively fixed place in front of the user's eyes so that the magnified display can stay in focus.
Since large virtual displays can be readily stored in the internal memory of the hand-held device, various solutions have been adapted to scroll relatively large amounts of data on a relatively small display. U.S. Pat. No. 3,976,995 (Reissue Pat. No. 32,365) teaches the use of a processing display which moves the message across the display in a continuous fashion so that the display needs to be only large enough to present a relatively small portion of the total message. While this approach may be useful to display simple sentences, it is not practical when displaying complex graphic information. And even with simple character displays, the user needs to wait patiently while the message is scrolling around.
Another common approach is to equip the device with scrolling keys, usually marked with arrows, to allow the operator to scroll the display in the desired direction. U.S. Pat. No. 5,774,109 discloses a hand-held electronic book with keyboard entry to facilitate the operator's scrolling of the information. The problem with such manual scrolling activity is that it adds a substantial burden to the operator because both hands must be used when reading a large document.
U.S. Pat. No. 5,311,203 discloses a hand-held viewing apparatus that determines the three dimensional direction in which it is pointing and automatically presents information to match the features visible in its field of view. This device is intended to observe, identify and locate stars or stellar constellations in an observed portion of the night sky. Once the exact direction of the device is measured, the device correlates the viewed objects and information stored in its database and displays identifying annotations near the corresponding objects. Since the device must correlate exactly between the database information with the observed objects, an exact spatial angle relative to earth is required, thus making the device prohibitively complex and expensive.
An article titled “Situated Information Spaces and Spatially Aware Palmtop Computers”, by George W. Fitzmaurice, Communication of the ACM, 36(7), July 1993, pp. 38-49, teaches how a small, portable and spatially aware palmtop computer can act as a window onto a 3D-situated information space. The article teaches the use of a complex sensor with six degrees of freedom, which provides complete orientation and position information so that the display can navigate the said information space. In an active map application suggested in the article, the experimental unit serves as an electronic information lens for a wall-mounted map. As the unit is moved around the map, information relating to the map's location just under the device is shown in the unit's display. Other applications like a computer-augmented library and portable surrogate office are disclosed, in which the unit provides information based on the position and orientation of the hand-held display. Like the previously discussed patent, the main disadvantage of this solution is the need of an elaborated 6D sensor which in turn requires the use of complex computing to determine both orientation and location of the moving device and correlate such location and orientation to the stored information space. In fact, the author's prototype required the use of an advanced desktop workstation to perform said computing.